misc.c

强实时嵌入式系统开发 Rev1.00 网上下载所得

/*
===============================================================================
| COPYRIGHT (C) 2004-2006 Haishen Ruan, All rights reserved.
| SUMMARY: 
|   Miscellaneous functions.
|
|
| LICENSE INFORMATION
|   RS-RTOS is free software; you can redistribute it and/or modify it under
|   terms of the GNU General Public License as published by the
|   Free Software Foundation; either version 2, or (at your option) any
|   later version.
|
|   RS-RTOS is distributed in the hope that it will be useful,
|   but WITHOUT ANY WARRANTY; without even the implied warranty of
|   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|   General Public License for more details.
|
|   You should have received a copy of the GNU General Public License
|   along with RS-RTOS; see file COPYING. If not, write to the Free Software
|   Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
|
|   As a special exception, including RS-RTOS header files in a file,
|   instantiating RS-RTOS generics or templates, or linking other files
|   with RS-RTOS objects to produce an executable application, does not
|   by itself cause the resulting executable application to be covered
|   by the GNU General Public License. This exception does not
|   however invalidate any other reasons why the executable file might be
|   covered by the GNU Public License.
|
|
| DESCRIPTION:
|   See http://www.RS-RTOS.org for documentation, latest information, license 
|   and contact details.
|   email:[e-mail]
=============================================================================*/
/*===========================================================================*/
#include "arch/arch.h"
#include "inc/const.h"
#include "inc/queue.h"
#include "inc/kernel.h"
#include "inc/memory.h"
#include "inc/ipc.h"
#include "inc/kapi.h"


typedef struct regs_context
{
    u16 task_entry;
    u16 task_fore;
    u16 task_arg;
} regs_t;


sp_t __stack_init(entry_t entry, arg_t arg, sp_t stack_base)
{
    regs_t idata* regs;

    regs = (regs_t idata*)stack_base;
    
    regs->task_entry = (u16)((u16)entry << 8 |
                             (u16)entry >> 8);

    regs->task_fore = (u16)((u16)__task_fore << 8 |
                            (u16)__task_fore >> 8);

    regs->task_arg = (u16)arg;

    return  (sp_t)regs + 3;
}


void __switch_to(sp_t __p_* curr_sp, sp_t next_sp)
{
    *curr_sp = (sp_t)SP;
    SP = next_sp;
}

/*===========================================================================*/